DOI: 10.1002/2016GL069527
论文题名: Quantifying entrainment in pyroclastic density currents from the Tungurahua eruption, Ecuador: Integrating field proxies with numerical simulations
作者: Benage M.C. ; Dufek J. ; Mothes P.A.
刊名: Geophysical Research Letters
ISSN: 0094-8937
EISSN: 1944-8668
出版年: 2016
卷: 43, 期: 13 起始页码: 6932
结束页码: 6941
语种: 英语
英文关键词: cauliflower bombs
; entrainment
; multiphase models
; pyroclastic density currents
; temperature
Scopus关键词: Rivers
; Sediment transport
; Temperature
; Direct measurement
; Entrainment coefficients
; Eulerian-Eulerian
; Multiphase model
; Pyroclastic density currents
; Thermal characteristics
; Thermal condition
; Tungurahua Volcano
; Air entrainment
; Brassica oleracea var. botrytis
英文摘要: The entrainment of air into pyroclastic density currents (PDCs) impacts the dynamics and thermal history of these highly mobile currents. However, direct measurement of entrainment in PDCs is hampered due to hazardous conditions and opaqueness of these flows. We combine three-dimensional multiphase Eulerian-Eulerian-Lagrangian calculations with proxies of thermal conditions preserved in deposits to quantify air entrainment in PDCs at Tungurahua volcano, Ecuador. We conclude that small-volume PDCs develop a particle concentration gradient that results in disparate thermal characteristics for the concentrated bed load (>600 to ~800 K) and the overlying dilute suspended load (~300–600 K). The dilute suspended load has effective entrainment coefficients 2–3 times larger than the bed load. This investigation reveals a dichotomy in entrainment and thermal history between two regions in the current and provides a mechanism to interpret the depositional thermal characteristics of small-volume but frequently occurring PDCs. ©2016. American Geophysical Union. All Rights Reserved. URL: https://www.scopus.com/inward/record.uri?eid=2-s2.0-84978878340&doi=10.1002%2f2016GL069527&partnerID=40&md5=2701a92127a76e0c451b44fb90bca318
Citation statistics:
资源类型: 期刊论文
标识符: http://119.78.100.158/handle/2HF3EXSE/9900
Appears in Collections: 科学计划与规划 气候变化与战略
There are no files associated with this item.
作者单位: School of Earth and Atmospheric Sciences, Georgia Institute of Technology, Atlanta, GA, United States
Recommended Citation:
Benage M.C.,Dufek J.,Mothes P.A.. Quantifying entrainment in pyroclastic density currents from the Tungurahua eruption, Ecuador: Integrating field proxies with numerical simulations[J]. Geophysical Research Letters,2016-01-01,43(13).